The invention relates to a filling system comprising a filling apparatus and a container arrangement inserted into the filling apparatus, wherein the container arrangement comprises:                a hose-like main line which comprises a feed line connected to a supply reservoir and a trunk line connected linearly downstream of the feed line, and        a plurality of target containers, in particular flexible bags which are each connected to the trunk line via a hose-like connecting line and wherein the filling apparatus comprises:        a support framework for mounting the target containers individually,        a valve support with a plurality of target container valves corresponding to the plurality of target containers and with which, it is possible, in each case, to control a volume flow through one of the connecting lines.        
The invention also relates to a filling method which makes use of a filling system of this type, wherein in a first filling step, through coordinated control of the valves of the valve support, one or more target containers are filled with fluid from the supply reservoir and at least one target container—which, below, is designated the residue container—remains unfilled.
Filling systems for filling manifolds are disclosed, for example, in EP 152 513 8B1. A manifold is taken here to mean a hose system which connects a plurality of containers to one another. Containers suitable for such filling systems include flexible bags, as well as rigid or semi-rigid containers, for example, bottles. The containers are linked via connecting lines to a common hose which, in the discussion below, is designated the trunk line. The trunk line is connected on one side to a feed hose and, on the other side, can be connected to a tapping-off hose. It can sometimes be difficult to draw a sharp border-line between the trunk line and the feed line or the discharge line in practice and the distinction should be understood, above all, in a functional sense in the context of the present description. The feed line essentially provides the connection to a supply reservoir, for example, a reservoir tank. The discharge line, where provided, serves to conduct away gas contained in the conductor line system or in the target containers during the filling process. The totality of the feed line, the trunk line and possibly the discharge line is here designated the main line.
For the filling, the manifold with the attached containers is placed into a special filling apparatus. There, the containers are arranged individually, in particular lying down or hanging in a support framework. The filling apparatus also comprises a valve support which can be fully or partially integrated into the aforementioned support framework. The valve support has a separately controllable valve, in particular a hose pinch valve, for each connecting line. With this, the connection of each target container to the trunk line can be established or prevented individually. Typically, the valve support also comprises a main valve with which the volume flow from the feed line to the trunk line is controlled and which, in practice, can be regarded as the functional border-line between the feed line and the trunk line.
For filling, in a preliminary flushing step, all the target container valves are closed and, with the main valve open (where provided), fluid is pumped from the supply reservoir into the trunk line until the trunk line is full, the gas in the trunk line being able to escape through the discharge line, when a discharge line is provided. The term pumping is to be understood in a broad sense in the present disclosure and comprises both true pumping processes and other, pressure-difference-related fluid transfer processes, e.g., those making use of gravity. Following the preliminary flushing, the target container valves are opened individually so that fluid can flow from the supply reservoir into the individual target containers. A fill level measurement can be carried out volumetrically or gravimetrically. In particular, the overall filling apparatus including the manifold can be positioned on an electronic balance, wherein the changes in the weighing values can provide information concerning the filling process and the corresponding electronic signals can be used as control signals in order to control the valves. As soon as a target container is filled, the corresponding target container valve is closed and the process is repeated with the next target container. After filling of the desired number of target containers, the containers are closed, for example, welded closed, and separated from the connecting lines.
A disadvantage of the known method is that a significant quantity of fluid remains in the trunk line and the connecting lines on the trunk line side of the target container valves. This disadvantage is more serious the more expensive the fluid is, wherein particularly in the biotechnology and medical domains, where manifolds are widely used, extremely costly fluids are handled.
From EP 0 632 775 B1, a filling system constructed with rigid pipelines is known which serves to fill bottles which are fed to the system by a conveyor belt feeding system in batches. For this purpose, the fluid for filling is firstly fed from a reservoir tank via a feed pipe into a horizontal distribution pipe from which a plurality of vertically downwardly extending outlet pipes, which are closed at the ends thereof with tip valves, emerge. Air in the distribution pipe can escape through an air outlet pipe connected at the end thereof. When preliminary flushing of the distribution pipe is carried out, the outlet pipes are also flushed out. Subsequently, the horizontal distribution pipe is emptied again in that the air outlet pipe is connected to a compressed air source and the inlet of the distribution pipe is decoupled from the feed pipe and is connected to a collecting tank. The fluid in the outlet pipes remains there, corresponding to a pre-dosing for the subsequent actual filling procedure. For this procedure, the input to the distribution pipe is closed and compressed air is fed to the end of the distribution pipe again, while at the same time, the tip valves of the outlet pipes are opened. The pre-dosed fluid in the outlet pipes is blown out into the bottles provided, which meanwhile have been positioned under the tip valves. At the same time, fluid gathering in the collecting tank, which meanwhile has been disconnected from the distribution pipe, is also blown, with the aid of compressed air, into the supply reservoir. This known system is not suitable for filling small volumes of costly, sterile fluids and is based, in essence, on initial excessive preliminary flushing and subsequent discarding of the residue. This necessarily requires the direct return of the residue to the supply reservoir; prior preparation (e.g. sterilization) or disposal of the residue is not economically viable due to the large volume of residue. However, return directly to the supply reservoir leads to a cyclic mixing of “old” and “fresh” fluid which, in the case of sensitive fluids, is not acceptable for hygiene reasons.
A system that is simplified relative to the aforementioned system is disclosed by DE 43 41 934 A1. Herein, the distribution pipe is always filled and pressurized; the pre-dosing into the outlet pipes is controlled via corresponding valves. The pressurization is achieved by pressurizing the supply reservoir.
A similar system in which, rather than a distribution pipe, a distribution tank is provided with outlet hoses attached thereto, is disclosed by DE 196 40 664 C1. Herein, the supply reservoir and the distribution tank are pressurized separately.